18887697 has 12 divisors (see below), whose sum is σ = 28887300. Its totient is φ = 11851008.

The previous prime is 18887689. The next prime is 18887699. The reversal of 18887697 is 79678881.

It can be written as a sum of positive squares in 2 ways, for example, as 13242321 + 5645376 = 3639^2 + 2376^2 .

It is not a de Polignac number, because 18887697 - 2³ = 18887689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18887699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61572 + ... + 61877.

It is an arithmetic number, because the mean of its divisors is an integer number (2407275).

Almost surely, 2^18887697 is an apocalyptic number.

18887697 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

18887697 is a deficient number, since it is larger than the sum of its proper divisors (9999603).

18887697 is a wasteful number, since it uses less digits than its factorization.

18887697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123472 (or 123469 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 54.

The square root of 18887697 is about 4345.9978140814. The cubic root of 18887697 is about 266.3133896545.

The spelling of 18887697 in words is "eighteen million, eight hundred eighty-seven thousand, six hundred ninety-seven".